Thiouracil

MINUTE CRYSTALS, PRISMS, OR WHITE OR PALE CREAM-COLORED POWDER

PRISMS FROM WATER OR ALC

VERY SLIGHTLY SOL IN WATER (1:2000); PRACTICALLY INSOL IN ETHER, ACIDS; READILY SOL IN ALKALINE SOLN

SLIGHTLY SOL IN ALC; SOL IN ANHYD HYDROGEN FLUORIDE

116.1 Ų [M-H]- [CCS Type: DT; Buffer gas: N2; Ionization: ESI-; Dataset: TOXCAST; Source Identifier: DTXSID4021347]

137.08 Ų [M+K]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

119.87 Ų [M+H]+

This chemical does not meet GHS hazard criteria for 5.6% (4 of 71) of reports.

Warning

H351 (94.4%): Suspected of causing cancer [Warning Carcinogenicity]

P203, P280, P318, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 71 reports by companies from 5 notifications to the ECHA C&L Inventory.

Danger

Chemical: 4(1H)-Pyrimidinone, 2,3-dihydro-2-thioxo-

Hazard Traits - Carcinogenicity

4(1H)-Pyrimidinone, 2,3-dihydro-2-thioxo-: Does not have an individual approval but may be used under an appropriate group standard

Carc. 2 (94.4%)

Acute toxicity (Oral) - Category 5

Acute toxicity (Oral) - Category 5

HEMORRHAGE, PETECHIAE, PURPURA.

THIOURACIL CAN INDUCE HEPATIC INJURY. /FROM TABLE/

THESE DRUGS /WHICH INCL THIOURACIL/ HAVE CAUSED NUMEROUS TOXIC SIDE REACTIONS PRINCIPALLY...DRUG FEVER, SKIN ERUPTIONS, & ARTERITIS.

MATERNAL ANTI-THYROID MEDICATION...HAS RESULTED...IN DEVELOPMENT OF FETAL GOITER, & OCCASIONALLY IN HYPOTHYROIDISM IN SOME NEONATE LEADING TO MENTAL RETARDATION. ... JUST OCCASIONALLY, GOITER IN AFFECTED INFANTS MAY OBSTRUCT AIR PASSAGE, & CAUSE RESPIRATORY DISTRESS.

For more Human Toxicity Excerpts (Complete) data for 2-THIOURACIL (6 total), please visit the HSDB record page.

Thiouracil

Group 2B: Possibly carcinogenic to humans

Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print)

2001

2000

DWARFISM & MENTAL RETARDATION...CAN BE PRODUCED IN RATS BY FEEDING DAMS...THIOURACIL...@ DIETARY LEVEL OF 1,000 PPM.

EIGHTY-ONE MICE OF 3 INBRED STRAINS (A, C57 & I) WERE ADMIN 0.1% THIOURACIL (TU) IN COMMERCIAL DIET FOR PERIODS OF UP TO 80 WK. IN 69 MICE EXAM, THYROIDAL FOLLICULAR CYSTS...FOUND & INTERPRETED BY AUTHORS AS NON-MALIGNANT LESIONS, SINCE THEY REGRESSED FOLLOWING WITHDRAWAL OF THIOURACIL...

OF 52 C STRAIN MICE (40 MALES & 12 FEMALES) ADMIN 0.37% THIOURACIL IN DIET FOR 6 MO FOLLOWED BY 0.5% FOR LIFE, LAST ANIMAL DIED @ 116 WK, & NODULAR HYPERPLASIS OF THYROID OCCURRED IN 28/39 MICE SURVIVING LONGER THAN 10 MO... IN (C57XCBA)F1 FEMALE MICE ADMIN 0.2% IN DIET...FROM 1-29 MO, HEPATOMAS...IN 6/21...ANIMALS.

NODULAR HYPERPLASIA OF THYROID WAS OBSERVED IN STANFORD ALBINO RATS OF BOTH SEXES AFTER ADMIN OF 0.1% THIOURACIL IN DIET FOR UP TO 45 WK. INCIDENCE IN MALES INCR FROM 3/10-11/20 AFTER TREATMENT FOR 29 & 45 WK, RESPECTIVELY. NO INCR...IN FEMALE RATS (3/10, COMPARED WITH 5/15) EXAM AFTER TREATMENT FOR 29 & 38 WK...

For more Non-Human Toxicity Excerpts (Complete) data for 2-THIOURACIL (9 total), please visit the HSDB record page.

Evaluation: There is inadequate evidence in humans for the carcinogenicity of thiouracil. There is sufficient evidence in experimental animals for the carcinogenicity of thiouracil. Overall evaluation: Thiouracil is probably carcinogenic to humans (Group 2B).

EARLIEST SIGN OF HYPOTHYROIDISM CALL FOR REDN IN DOSE; IF BY CHANCE THEY HAVE ADVANCED TO POINT OF DISCOMFORT, THYROID HORMONE CAN BE GIVEN TO HASTEN RECOVERY. FULL DOSE OF 120-180 MG DAILY OF THYROID OR EQUIV OF TYHROXINE OR TRIIODOTHYRONINE FOR WK WILL USUALLY SUFFICE. /ANTI-THYROID DRUGS/

ANTITHYROID DRUGS INHIBIT FORMATION OF THYROID HORMONE LARGELY BY INTERFERING WITH INCORPORATION OF IODINE INTO ORGANIC FORM. THIS IMPLIES THAT THEY INTERFERE WITH OXIDN OF IODIDE ION, BUT ELUCIDATION OF DETAILED MECHANISM... HAMPERED BY INCOMPLETE UNDERSTANDING OF IODIDE-OXIDIZING SYSTEM OF...GLAND. /ANTITHYROID DRUGS/

THIOAMIDE DERIV DO NOT HAVE PERMANENT EFFECT UPON THYROID GLAND BUT INHIBIT HORMONE SYNTHESIS & SECRETION UNTIL SPONTANEOUS REMISSION OCCURS DURING COURSE OF DISEASE. /THIOAMIDE DERIV/

IN HOMOGENIZED RAT LIVER PREPN FROM FEMALE HOLTZMAN RATS, 28-35% OF THIOURACIL WAS METABOLIZED WITHIN 3 HR. PATHWAY FOR BREAKDOWN OF THIOURACIL WAS SUGGESTED TO BE AS FOLLOWS: URACIL; BETA-UREIDOPROPIONIC ACID, WHICH WAS FURTHER METABOLIZED TO BETA-ALANINE; AMMONIA & CARBON DIOXIDE...

Agents that are used to treat hyperthyroidism by reducing the excessive production of thyroid hormones.

Drugs used to cause dilation of the blood vessels.

DRUG TRANSMISSION TO FETUS: TIME TO APPEAR IN FETUS 10 MIN; TIME TO FETAL/MATERNAL CONCN EQUILIBRIUM 40 MIN; FETAL/MATERNAL CONCN RATIO 1.0 /FROM TABLE/

/IN RATS/ ACCUMULATION OF (35)S LABEL WAS FASTER & OCCURRED TO GREATER EXTENT FROM SMALLER DOSE, SUGGESTING PRESENCE OF SATURABLE TRANSPORT MECHANISM. SIMILAR STUDIES WITH (14)C-THIOURACIL HAVE SHOWN ACCUM OF RADIOACTIVITY IN BOTH MATERNAL & FETAL THYROID TISSUES OF RABBITS...

...WITH BOTH LARGE (39 UMOL) & SMALL (1.2 UMOL) DOSES OF (35)S-THIOURACIL, CONSIDERABLE ACCUM OF BOTH TOTAL RADIOACTIVITY & UNMETABOLIZED (35)S-THIOURACIL OCCURS IN THYROID TISSUE RELATIVE TO PLASMA /IN RATS/.

THIOURACIL IS ABSORBED FROM GI TRACT IN RATS... IN RATS ADMIN 5 MG BY IV INJECTION, 30% OF THIOURACIL...RECOVERED FROM CARCASSES AFTER 3 HR & ONLY TRACES AFTER 24 HR.

For more Absorption, Distribution and Excretion (Complete) data for 2-THIOURACIL (7 total), please visit the HSDB record page.

CHEM INT FOR IOTHIOURACIL SODIUM- AN ANTITHYROID AGENT

MEDICATION

MEDICATION (VET)

(1972) No Data

(1975) No Data

(1972) No Data

(1975) No Data

(1974) PROBABLY GREATER THAN 4.54X10+5 GRAMS

(1975) PROBABLY GREATER THAN 4.54X10+5 GRAMS

CONDENSATION OF ETHYL FORMYLACETATE WITH THIOUREA

PREPD BY CONDENSING ETHYL FORMYLACETATE WITH THIOUREA: WHEELER, LIDDLE, AM CHEM J 40, 550 (1908).

4(1H)-Pyrimidinone, 2,3-dihydro-2-thioxo-: ACTIVE

THIOAMIDE DERIV USED IN THIS COUNTRY ARE PROPYLTHIOURACIL, METHIMAZOLE, & METHYLTHIOURACIL. THESE DRUGS HAVE REPLACED PARENT COMPD, THIOURACIL, WHICH IS MORE TOXIC.